English
Related papers

Related papers: The Cosmological Optical Convergence: Extragalacti…

200 papers

In this work, we use two different methods to determine the opacity of the TeV gamma-rays caused by the extragalactic background light (EBL) via e-e+ production due to photon-photon interaction. The first method, Model-Dependent Approach,…

High Energy Astrophysical Phenomena · Physics 2020-04-07 K. K. Singh , P. J. Meintjes

The Extragalactic Background Light (EBL) as an integrated light from outside of our Galaxy includes information of the early universe and the Dark Ages. We analyzed the spectral data of the astrophysical diffuse emission obtained with the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Kohji Tsumura , Toshio Matsumoto , Shuji Matsuura , Itsuki Sakon , Takehiko Wada

Observations of distant gamma-ray sources are hindered by the presence of the extragalactic background light (EBL). In order to understand the physical processes that result in the observed spectrum of sources, it is imperative that a good…

High Energy Astrophysical Phenomena · Physics 2017-06-01 Thomas Armstrong , Anthony M. Brown , Paula M. Chadwick

Very high energy (VHE, E > 30 GeV) gamma-rays are absorbed via interaction with low-energy photons from the extragalactic background light (EBL) if the involved photon energies are above the threshold for electron-positron pair creation.…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-13 D. Mazin

I present the results of a new approach to the intensity and photon density spectrum of the intergalactic background light as a function of redshift using observational data obtained in many different wavelength bands from local to deep…

High Energy Astrophysical Phenomena · Physics 2013-02-11 Floyd W. Stecker

The extragalactic background light (EBL) consists of integrated light from all sources of emission throughout the history of the universe. At near-infrared wavelengths, the EBL is dominated by stellar emission across cosmic time; however,…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-09 Yun-Ting Cheng , Tzu-Ching Chang

The flux of extragalactic gamma rays is attenuated through interactions with optical and infrared photons of the extragalactic background light (EBL). The EBL is an isotropic, diffuse photon field that is difficult to measure directly at…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-01 Sara Porras-Bedmar , Manuel Meyer

The study of the extragalactic background light (EBL) in the optical and near infrared has received a lot of attention in the last decade, especially near a wavelength of $\lambda\approx 3.4\operatorname{\mu m}$, with remaining tension…

The Extragalactic Background Light (EBL) causes attenuation of the VHE spectra of extragalactic sources, via pair-production. The amount of attenuation depends on the distance of the source, i.e. on the integration over the line of sight…

Cosmology and Nongalactic Astrophysics · Physics 2009-09-01 Bagmeet Behera , Stefan J. Wagner

I review the constraints imposed by the observed extragalactic background light (EBL) on the history of the stellar birthrate in galaxies. At faint magnitudes, the logarithmic slope of the galaxy counts is flatter than 0.4 in all seven…

Astrophysics · Physics 2009-10-31 Piero Madau

Recent observations of the TeV gamma-ray spectra of the two closest active galactic nuclei (AGNs), Markarian 501 (Mrk 501) and Markarian 421 (Mrk 421), by the Whipple and HEGRA collaborations have stimulated efforts to estimate or limit the…

Astrophysics · Physics 2009-10-31 Vladimir V. Vassiliev

We present the method and observations for the measurement of the Extragalactic Background Light (EBL) utilizing the shadowing effect of a dark cloud. We measure the surface brightness difference between the opaque cloud core and its…

Cosmology and Nongalactic Astrophysics · Physics 2017-07-26 K. Mattila , K. Lehtinen , P. Väisänen , G. von Appen-Schnur , Ch. Leinert

The extragalactic background light (EBL), from ultraviolet to infrared wavelengths, is predominantly due to emission from stars, accreting black holes and reprocessed light due to Galactic dust. The EBL can be studied through the imprint it…

High Energy Astrophysical Phenomena · Physics 2017-11-29 Abhishek Desai , Marco Ajello , Nicola Omodei , Dieter Hartmann , Alberto Dominguez , Vaidehi Paliya , Kari Helgason , Justin Finke , Manuel Meyer

We present $\gamma$-ray optical-depth calculations from a recently published extragalactic background light (EBL) model built from multiwavelength galaxy data from the Hubble Space Telescope Cosmic Assembly Near-Infrared Deep Extragalactic…

We combine the recent estimate of the contribution of galaxies to the 3.6 micron intensity of the extragalactic background light (EBL) with optical and near-infrared (IR) galaxy counts to set new limits on intrinsic spectra of some of the…

Astrophysics · Physics 2009-11-13 F. Krennrich , E. Dwek , A. Imran

The optical/far-IR extragalactic background light (EBL) from both resolved and unresolved extragalactic sources is an indicator of the total luminosity of cosmic structures, as the cumulative emission from young and evolved galactic…

Astrophysics · Physics 2007-05-23 Piero Madau , Francesco Haardt , Lucia Pozzetti

Deep optical and near-infrared galaxy counts are utilized to estimate the extragalactic background light (EBL) coming from normal galactic light in the universe. Although the slope of number-magnitude relation of the faintest counts is flat…

Astrophysics · Physics 2009-11-06 T. Totani , Y. Yoshii , F. Iwamuro , T. Maihara , K. Motohara

The extragalactic background light (EBL) is the relic emission of all processes of structure formation in the Universe. About half of this background, called the Cosmic Infrared Background (CIB) is emitted in the 8-1000 microns range, and…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-10 Matthieu Béthermin , Hervé Dole

This study investigates the impact of the fluctuations in the extra galactic background light (EBL) on the attenuation of the hard $\gamma$-ray spectra of distant blazars. EBL fluctuations occur on the scales up to 100 Mpc and are caused by…

High Energy Astrophysical Phenomena · Physics 2017-03-22 A. M. Kudoda , A. Faltenbacher

We have previously calculated the intergalactic background light (IBL) as a function of redshift in the far ultraviolet to near infrared range, based purely on data from deep galaxy surveys. Here we utilize similar methods to determine the…

High Energy Astrophysical Phenomena · Physics 2016-08-17 Floyd W. Stecker , Sean T. Scully , Matthew A. Malkan
‹ Prev 1 3 4 5 6 7 10 Next ›